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JavaScript, elegant way to check nested object properties for null/undefined [duplicate]
a "problem" which i have every now and then is that i have an object e.g. user = {} and through the course of using the app this gets populated. Let's say somwhere, after an AJAX call or something i do this:
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Finding what methods a Python object has
...t an AttributeError, you can use this instead:
getattr( is intolerant of pandas style python3.6 abstract virtual sub-classes. This code does the same as above and ignores exceptions.
import pandas as pd
df = pd.DataFrame([[10, 20, 30], [100, 200, 300]],
columns=['foo', 'bar',...
How to properly document S4 class slots using Roxygen2?
For documenting classes with roxygen(2), specifying a title and description/details appears to be the same as for functions, methods, data, etc. However, slots and inheritance are their own sort of animal. What is the best practice -- current or planned -- for documenting S4 classes in roxygen2?
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Are there any standard exit status codes in Linux?
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8 bits of the return code and 8 bits of the number of the killing signal are mixed into a single value on the return from wait(2) & co..
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/wait.h>
#...
What does it mean when git says a file “needs update”?
...laining this marked as a TODO. If someone could explain A) what it means; and B) how to fix it, I would be extremely grateful.
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Batch file to copy files from one folder to another folder
... copy against the original. slower, but for the paranoid.
/h - copy system and hidden files.
/k - copy read-only attributes along with files. otherwise, all files become read-write.
/x - if you care about permissions, you might want /o or /x.
/y - don't prompt before overwriting existing files.
/z -...
Export query result to .csv file in SQL Server 2008
...ight, there is a drop
down box called Output Format
Choose Comma Delimited and click OK
Here's a full screen version of that image, below
This will show your query results as comma-delimited text.
To save the results of a query to a file: Ctrl + Shift + F
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Insert into a MySQL table or update if exists
...m what I've found, this method is less problematic for auto-increment keys and other unique key collisions than REPLACE INTO, and it is more efficient.
– Andrew Ensley
May 11 '12 at 21:27
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What is the purpose of the -m switch?
...line of the Rationale section of PEP 338 says:
Python 2.4 adds the command line switch -m to allow modules to be located using the Python module namespace for execution as scripts. The motivating examples were standard library modules such as pdb and profile, and the Python 2.4 implementation is...
Batch files : How to leave the console window open
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If that is really all the batch file is doing, remove the cmd /K and add PAUSE.
start /B /LOW /WAIT make package
PAUSE
Then, just point your shortcut to "My Batch File.bat"...no need to run it with CMD /K.
UPDATE
Ah, some new info...you're trying to do it from a pinned shortcut on the...